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ScienceDaily (July 11, 2012) — The volume of a small brain region influences one’s predisposition for altruistic behavior. Researchers from the University of Zurich show that people who behave more altruistically than others have more gray matter at the junction between the parietal and temporal lobe, thus showing for the first time that there is a connection between brain anatomy, brain activity and altruistic behavior.

Why are some people very selfish and others very altruistic? Previous studies indicated that social categories like gender, income or education can hardly explain differences in altruistic behavior. Recent neuroscience studies have demonstrated that differences in brain structure might be linked to differences in personality traits and abilities. Now, for the first time, a team of researchers from the University of Zurich headed by Ernst Fehr, Director of the Department of Economics, show that there is a connection between brain anatomy and altruistic behavior.

To investigate whether differences in altruistic behavior have neurobiological causes, volunteers were to divide money between themselves and an anonymous other person. The participants always had the option of sacrificing a certain portion of the money for the benefit of the other person. Such a sacrifice can be deemed altruistic because it helps someone else at one’s own expense. The researchers found major differences in this respect: Some participants were almost never willing to sacrifice money to benefit others while others behaved very altruistically.

More gray matter

The aim of the study, however, was to find out why there are such differences. Previous studies had shown that a certain region of the brain — the place where the parietal and temporal lobes meet — is linked to the ability to put oneself in someone else’s shoes in order to understand their thoughts and feelings. Altruism is probably closely related to this ability. Consequently, the researchers suspected that individual differences in this part of the brain might be linked to differences in altruistic behavior. And, according to Yosuke Morishima, a postdoctoral researcher at the Department of Economics at the University of Zurich, they were right: “People who behaved more altruistically also had a higher proportion of gray matter at the junction between the parietal and temporal lobes.”

Differences in brain activity

The participants in the study also displayed marked differences in brain activity while they were deciding how to split up the money. In the case of selfish people, the small brain region behind the ear is already active when the cost of altruistic behavior is very low. In altruistic people, however, this brain region only becomes more active when the cost is very high. The brain region is thus activated especially strongly when people reach the limits of their willingness to behave altruistically. The reason, the researchers suspect, is that this is when there is the greatest need to overcome man’s natural self-centeredness by activating this brain region.

Ernst Fehr adds: “These are exciting results for us. However, one should not jump to the conclusion that altruistic behavior is determined by biological factors alone.” The volume of gray matter is also influenced by social processes. According to Fehr, the findings therefore raise the fascinating question as to whether it is possible to promote the development of brain regions that are important for altruistic behavior through appropriate training or social norms.

ScienceDaily (July 11, 2012) — When humans learn, their brains relate new information with past experiences to derive new knowledge, according to psychology research from The University of Texas at Austin.

The study, led by Alison Preston, assistant professor of psychology and neurobiology, shows this memory-binding process allows people to better understand new concepts and make future decisions. The findings could lead to better teaching methods, as well as treatment of degenerative neurological disorders, such as dementia, Preston says.

“Memories are not just for reflecting on the past; they help us make the best decisions for the future,” says Preston, a research affiliate in the Center for Learning and Memory, which is part of the university’s College of Natural Sciences. “Here, we provide a direct link between these derived memories and the ability to make novel inferences.”

The paper was published online in July in the journal Neuron. The authors include University of Texas at Austin researchers Dagmar Zeithamova and April Dominick.

In the study, 34 subjects were shown a series of paired images composed of different elements (for example, an object and an outdoor scene). Each of the paired images would then reappear in more presentations. A backpack, paired with a horse in the first presentation, would appear alongside a field in a later presentation. The overlap between the backpack and outdoor scenery (horse and field) would cause the viewer to associate the backpack with the horse and field. The researchers used this strategy to see how respondents would delve back to a recent memory while processing new information.

Using functional Magnetic Resonance Imaging (fMRI) equipment, the researchers were able to look at the subjects’ brain activity as they looked at image presentations. Using this technique, Preston and her team were able to see how the respondents thought about past images while looking at overlapping images. For example, they studied how the respondents thought about a past image (a horse) when looking at the backpack and the field. The researchers found the subjects who reactivated related memories while looking at overlapping image pairs were able to make associations between individual items (i.e. the horse and the field) despite the fact that they had never studied those images together.

To illustrate the ways in which this cognitive process works, Preston describes an everyday scenario.

Imagine you see a new neighbor walking a Great Dane down the street. At a different time and place, you may see a woman walking the same dog in the park. When experiencing the woman walking her dog, the brain conjures images of the recent memory of the neighbor and his Great Dane, causing an association between the dog walkers to be formed in memory. The derived relationship between the dog walkers would then allow you to infer the woman is also a new neighbor even though you have never seen her in your neighborhood.

“This is just a simple example of how our brains store information that goes beyond the exact events we experience,” Preston says. “By combining past events with new information, we’re able to derive new knowledge and better anticipate what to expect in the future.”

During the learning tasks, the researchers were able to pinpoint the brain regions that work in concert during the memory-binding process. They found the hippocampal-ventromedial prefrontal cortex (VMPFC) circuit is essential for binding reactivated memories with current experience.

Proponents of Neuro-Linguistic Programming (NLP) have long claimed that it is possible to tell whether a person is lying from their eye movements. Research published July 11 in the journal PLoS ONE reveals that this claim is unfounded, with the authors calling on the public and organisations to abandon this approach to lie detection.

For decades many NLP practitioners have claimed that when a person looks up to their right they are likely to be lying, whilst a glance up to their left is indicative of telling the truth.

Professor Richard Wiseman (University of Hertfordshire, UK) and Dr Caroline Watt (University of Edinburgh, UK) tested this idea by filming volunteers as they either lied or told the truth, and then carefully coded their eye movements. In a second study another group of participants was asked to watch the films and attempt to detect the lies on the basis of the volunteers’ eye movements.

“The results of the first study revealed no relationship between lying and eye movements, and the second showed that telling people about the claims made by NLP practitioners did not improve their lie detection skills,” noted Wiseman.

A final study involved moving out of the laboratory and was conducted in collaboration with Dr Leanne ten Brinke and Professor Stephen Porter from the University of British Columbia, Canada. The team analysed films of liars and truth tellers from high profile press conferences in which people were appealing for missing relatives or claimed to have been the victim of a crime.

“Our previous research with these films suggests that there are significant differences in the behaviour of liars and truth tellers,” noted Dr Leanne ten Brinke. “However, the alleged tell-tale pattern of eye movements failed to emerge.”

“A large percentage of the public believes that certain eye movements are a sign of lying, and this idea is even taught in organisational training courses. Our research provides no support for the idea and so suggests that it is time to abandon this approach to detecting deceit” remarked Watt.

ScienceDaily (July 11, 2012) — Is anxiety related to premature aging? A new study by researchers at Brigham and Women’s Hospital (BWH) shows that a common form of anxiety, known as phobic anxiety, was associated with shorter telomeres in middle-aged and older women. The study suggests that phobic anxiety is a possible risk factor for accelerated aging.

The study will be electronically published on July 11, 2012 in PLoS ONE.

Telomeres are DNA-protein complexes at the ends of chromosomes. They protect chromosomes from deteriorating and guard the genetic information at the ends of chromosomes during cell division. Telomeres are considered markers of biological or cellular aging. Shortened telomeres have been linked to increased risk of cancers, heart disease, dementia and mortality.

In this large, cross-sectional study, researchers had obtained blood samples from 5,243 women, age 42 to 69 years, who were participants in the Nurses’ Health Study. Using the samples, the researchers analyzed telomere lengths, as well as the participants’ concurrent self-reports regarding phobic symptoms on a validated questionnaire.

Having a high phobic anxiety level was associated with significantly shorter telomere lengths. The difference in telomere lengths for women who were highly phobic vs. not was similar to what was seen for an additional six years of age.

“Many people wonder about whether — and how — stress can make us age faster,” said Olivia Okereke, MD, MS, BWH Department of Psychiatry, study author. “So, this study is notable for showing a connection between a common form of psychological stress — phobic anxiety — and a plausible mechanism for premature aging. However, this type of study design cannot prove cause-and-effect or which problem came first — the anxiety or shorter telomeres.”

The findings pave the way for further prospective investigations relating anxiety to telomere length change.